Open development.services.yml in the sites folder and add the following block (to disable twig cache):

# vim sites/development.services.yml

parameters:
twig.config:
debug : true
auto_reload: true
cache: false

Afterwards you have to rebuild the Drupal cache. Otherwise your website will encounter an unexpected error on page reload. This can be done by visiting the following URL from your Drupal 8 website:
http://yoursite/core/rebuild.php

This directory contains configuration to be imported into your Drupal site. To make this configuration active, visit admin/config/development/configuration/sync. For information about deploying configuration between servers, see https://www.drupal.org/documentation/administer/config
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Working With Twig Templates